Learn to make your own ray diagrams using these 101 Diagramss as your reference! We draw this kind of diagram to explain reflection in a plane mirror (a flat mirror). In a ray diagram, the mirror is drawn a straight line with thick hatchings to show which side has the reflective coating. The light rays are drawn as solid straight lines, each with an arrowhead to show the direction of travel. Light rays that appear to come from behind the mirror are shown as dashed straight lines. Take a look at the following example of simple ray diagram posted below.

A ray diagram is a diagram that traces the path that light takes in order for a person to view a point on the image of an object. On a simple ray diagram, rays (lines with arrows) are drawn for the incident ray and the reflected ray. Complex objects such as people are often represented by stick figures or arrows. In such cases it is customary to draw rays for the extreme positions of such objects. Make sure that the incident rays (the solid lines) obey the law of reflection: the angle of incidence equals the angle of reflection. Extend two lines behind the mirror. They cross where the image appears to come from. More examples of the 101 Diagramss are posted below.



Drawing ray diagrams is pretty easy. Merely duplicate the two setups below onto a blank sheet of paper, grab a ruler/straightedge, and begin. If necessary, refer to the four-step procedure listed above. The line of sight principle suggests that in order to view an image of an object in a mirror, a person must sight along a line at the image of the object. When sighting along such a line, light from the object reflects off the mirror ray diagram lens according to the law of reflection and travels to the person’s eye. More various ray diagrams are posted below.



Ray diagrams can be particularly useful for determining and explaining why only a portion of the image of an object can be seen from a given location. Try to make your own ray diagram by using these 101 Diagramss as examples!